Immunotherapy (Post #17)

Hi! Welcome back to the Founder's Blog after a little over a month! It is officially summer. After a short break, I will be posting 3 times every week from mid-July to September-end, so you'll have a lot to read during the school break! In today's post, we'll be discussing immunotherapy: what it is and some new research and treatment changes involving it.

Immunotherapy, like it sounds, is a treatment that utilizes a patient's own immune cells to fight cancer. To understand how immunotherapy works, we first have to understand a little bit more about how cancer works. Usually, when abnormal cells are formed, immune cells called 'T-Cells' identify them and destroy them. However, cancer cells are able to avoid this destruction in three ways: by adapting their surface molecules to blend in with healthy cells, releasing chemical signals that weaken immune cells, and lastly, by activating "off switches" that stop T Cells from recognizing them.

There are a few types of immunotherapy used in practice:

• Immune Checkpoint Inhibitors

  • T-Cells have "checkpoints" (example: PD-1 protein) that stop them from attacking healthy cells

  • cancer cells try to escape attack by binding to these checkpoints so that they become inactive

  • one common cancer surface protein used is the PD-L1 protein

  • the PD-L1 cancer protein binds to the PD-1 T-cell protein, making the T-Cell "turn off"

  • immune checkpount inhibitors block PD-1 or PD-L1 so that they cannot bind to each other

  • this blocking allows T-Cells to stay active and recognize + destroy cancer cells

• Car-T Cell Therapy

  • full name: Chimeric Antigen Receptor T-Cell Therapy

  • personalized treatment where a patient's own immune cells are modified to better recognize cancer

  • doctors remove T-Cells from patients' blood

  • scientists modify the T-Cells by adding a new gene

  • this new gene leads to "CAR" receptors being formed

  • CAR receptors allow the cell to recognize a specific protein on cancer cells

  • modified T-Cells are multiplied and put back into the patient's blood

  • the Car-T cells are able to better recognize and destroy cancer cells

• Monoclonal Antibodies

  • lab-made versions of immune system proteins

  • recognize and attach to specific molecules on cancer cells

  • there are 3 ways in which monoclonal antibodies may work:

    • recognize and attach to cancer cells, leading immune system to destroy the cell

    • block proteins that the cancer tumor needs to grow, slowing its growth rate

    • delivering treatments like drugs, radiation particles, or toxins directly to the cancer tumor

• Cancer Vaccines

  • discussed in an earlier post (check that out for extra info!)

  • not preventative like other vaccines, cancer vaccines treat already existing cancer

  • scientists put molecules called "tumor antigens" into the blood (cancer tumors have these antigens on their surface)

  • the immune system learns to recognize these tumor antigens and destroys them

  • when the immune system finds tumor antigens on the cancer tumor in the patient, it is able to recognize and destroy the cancer cells

• Oncolytic Virus Therapy

  • uses modified viruses that can infect and destroy cancer cells

  • scientists modify a virus in the lab so that it cannot infect healthy cells

  • the virus is released into the patient's body, near the cancer tumor

  • the virus enters cancer cells and reproduces

  • cancer cells 'lyse', meaning they burst and die

  • bursting cancer cells release tumor markers

  • the immune system recognizes these released tumor markers and attacks other nearby cancer cells

• Cytokine Therapy

  • cytokines are glycoproteins produced by immune cells

  • they act as messengers in the body, allowing immune cells to communicate

  • scientists make artificial cytokines in the lab

  • these cytokines are introduced to patients' body

  • they send "danger signals" to immune cells

  • immune cells attack cancer cells more aggressively

As more research is being done on these treatments, doctors are beginning to combine multiple immunotherapy types. Personalized treatment is also being used to decide which type of immunotherapy will suit a patient best.

Thanks for reading this week's issue! See you in a few weeks for our new 3 posts schedule!

Information Citations:

“Immune Checkpoint Inhibitors.” Cancer.Gov, 7 Apr. 2022, https://www.cancer.gov/about-cancer/treatment/types/immunotherapy/checkpoint-inhibitors

National Cancer Institute. “CAR T Cells: Engineering Immune Cells to Treat Cancer.” National Cancer Institute, Cancer.gov, 26 Feb. 2025, https://www.cancer.gov/about-cancer/treatment/research/car-t-cells.

“Head and Neck Cancer - Cancer Research Institute.” Cancer Research Institute, 29 Apr. 2025, https://www.cancerresearch.org/immunotherapy-by-cancer-type/head-and-neck-cancer.

“Cancer Treatment Vaccines - Immunotherapy.” Cancer.Gov, 24 Sept. 2019, https://www.cancer.gov/about-cancer/treatment/types/immunotherapy/cancer-treatment-vaccines

Spindler, Shana. “Oncolytic Virus Disrupts Immune-Blocking Protein - NCI.” Www.Cancer.Gov, 12 Oct. 2023, https://www.cancer.gov/news-events/cancer-currents-blog/2023/oncolytic-virus-blocking-tgf-beta

“Improving T-Cell-Based Immunotherapy Treatments for Solid Tumors - NCI.” Www.Cancer.Gov, 1 Nov. 2023, https://www.cancer.gov/news-events/press-releases/2023/cytokines-supercharge-t-cell-therapies

Image Citations:

Biosystems, Logos. Figure 1. Mechanism of CAR-T Cell Therapy. 12 Mar. 2025, https://logosbio.com/car-t-cell-therapy-redesigning-the-immune-system-to-fight-cancer/.